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How can blast-furnace slag be used as a raw material for cement?

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Cement The cement-making process, from crushing and grinding of raw materials, through roasting of the ground and mixed ingredients, to final cooling and storing of the finished product.

Blast-furnace slag is utilized as a raw material for cement by first undergoing rapid chilling to create granulated slag, which serves as the foundation for various constructional cements.1

This granulated material is typically incorporated into cement through the following methods:

Portland Blast-Furnace Slag Cement: This is produced by intimately intergrinding a mixture of portland cement clinker and granulated blast-furnace slag. In English-speaking countries, these mixtures can contain up to 65 percent slag.21
Regional Variations: Different proportions are used internationally, such as the German Eisenportlandzement (up to 40 percent slag) and Hochofenzement (up to 85 percent slag).1
Supersulfated Cement: This type consists of granulated slag mixed with 10 to 15 percent hard-burned gypsum or anhydrite and a small amount of portland cement.1

These slag-based cements generally share properties with standard portland cement but often feature lower lime content and higher silica and alumina levels. Notably, cements with higher slag content provide increased resistance to chemical attack.1